1. Field of the Invention
This invention relates to burner supplying gas or liquid fuel for combustion in a furnace.
2. Description of the Prior Art
A dual fuel burner is disclosed in U.S. Pat. No. 4,221,558.
The '558 apparatus performs well over a wide range of temperatures and fuel flow rates, using oil or gas as fuel; the apparatus performs particularly well when used in a deep cup formed in the furnace wall with the burner tip recessed from the cup surface.
A disadvantage attendant to the '558 apparatus is that when oil is the fuel, oil may accumulate in the burner tip during cold start-up. Additionally, when oil is the fuel, for best operation a separate blower is sometimes required to force atomizing air through the burner housing. Also, when gas is the fuel, the '558 apparatus does not work entirely satisfactorily when used in a shallow cup formed in the furnace wall.